Introduction

The objectives for this lab are to get you to access the University of Utah’s Center for High Performance Computing (CHPC) OnDemand service for this class. We’ll cover:

  1. Accessing the CHPC
  2. Transferring files
  3. Starting Quantumn GIS

CHPC account

To start, you’ll need an account with the CHPC. To do this, go to the following link and enter the token that was sent out just before the start of class. The class number for the CHPC is ‘GEOG5670’ (even if you are enrolled in GEOG 6670):

https://www.chpc.utah.edu/role/user/student.php?class=GEOG5670

Once you receive confirmation of your account, you can proceed with the rest of this lab.

Off-campus access

If you would like to use this service from an off campus location, you will need a VPN to connect to the CHPC. The recommended VPN is Palo Alto’s Global Protect client. Details of how to install this are given in this article:

https://uofu.service-now.com/it?id=uu_kb_article&sys_id=3b8f74b81ba2b810247ceac0604bcb07

GlobalProtect installation instructions:

  • Using the device you’d like to connect to the VPN, visit https://vpn.utah.edu to install GlobalProtect (if you’re using a university-managed device, it may be necessary to contact your local IT desktop support staff). For CSBS managed computers, you can download and install this through the CSBS Self Service app.
  • Select the GlobalProtect agent for your computer (Windows 32bit, Windows 64bit, or Mac 32/64).
  • Once the msi/pkg file has been downloaded, launch the file to install.
  • If prompted, enter vpn.utah.edu as your portal address.
  • Rebooting your computer after installation is recommended.
  • Upon rebooting your device, you may receive a pop-up window prompting the utilization of GlobalProtect. Please remember, VPN use is not required on devices with an on-site IP address, or when accessing many university resources.
  • Duo 2FA users will receive an authentication prompt on their Duo-registered mobile device.
    • The username is your uNID.
    • The password is your university password

Accessing OnDemand

To access the class OnDemand page, just enter the following address in your browser

https://ondemand-class.chpc.utah.edu/pun/sys/dashboard/batch_connect/sys/GEOG5670_desktop/

You will be asked for your login credentials and two-factor authentication. Once you’ve enter these, the following page will appear.

OnDemand class landing page

There are various options here to change the node and cluster that are used and to change the amount of time requested for the current session. Do not change these, and just scroll to the bottom and click [Launch]. You can check the box to receive an email when the service starts - this can be useful during busy times when you may have a short wait to access the server.

There will be a short wait while the service starts, and when you see this screen appear (with the word ‘Running’ in the green header), your desktop is ready for use:

Seervice start page

At this point, if you click [Launch GEOG5670 desktop], a new window will open:

Virtual desktop

Starting OnDemand QGIS

To start QGIS in your virtual desktop you will need to open a terminal. At the top of the screen you should see a small black icon, just next to the FireFox icon.

Terminal icon

Click this to open a terminal:

Terminal

Then enter the following lines:

module load qgis/3.10
qgis

Which will open the interface to QGIS:

OnDemand QGIS window

Transferring files to the CHPC clusters

The CHPC has a central store for all user files. You can add these via ftp, or more simply by opening a file browser. If you go back to the previous page, you will see several drop down menus at the top:

File access

Click on [Files] then [Home Directory] to open a new page with a browser for your directory. Here you can make folders and drag and drop files to upload them. Once they are there, you will be able to access them from QGIS (and later from GRASS GIS).

File browser

To test this, go to the Documents folder and create a new directory called geog5670. Now transfer the forestry.zip file here. To unzip this, go back to your virtual desktop, and open a file browser by clicking on the computer icon on the desktop. Navigate to your new folder (geog5670) and then right click on the zip file. Click on ‘Extract to…’ and then ‘Extract’. Once this is finished, go back to QGIS and we will add in a layer from this file.

In the QGIS interface, go to the [Layer] menu at the top, then [Add Layer] -> [Add Raster Layer]. In the next window, click the three dots […] to open a browser, and navigate to the forestry folder. Click on the file basic_map.tif to import it.